Apparatus for the manufacture of artificial silk.



G. GUADAGNI.

E MANUFACTURE OF ARTIFICIAL SILK.

APPARATUS FOR TH v APPLIOATIOITI FILED JUNE 1;, 190 977,863. PatentedDec. 6, 1910.

a sums-sham 1.

, G. GUADAGNI.

APPARATUS FOR THE MANUFACTURE OF ARTIFICIAL SILK.

VAPPLIOATION FILED JUNE 14, 1909'.

2 BHBETS-BHEBT 2.

' Patented Dec. 6, 1910.

sTAirEs PAEFENT oriuon GIUSEPPE GUADAGNI, 0F PAVIA, ITALY.

Specification of Letters Patent. Original application filed July 15,1908, Serial No. 443,655. Dividedand this application filed June 14,1909.

APPARATUS FOR THE MANUFACTURE OF ARTIFICIAL SILK.

I Patented Dec. 6, 1910.

Serial No. 502,065.

hereby declare thefollowing to be a full,

clear, and exact description of the invention, such as will enableothers skilled in the art to which it appertainsto make and use thesame, reference being had to the" accompanying drawings, and to lettersor figures of reference marked thereon, which form a part ofthisspecification.

My invention relates to the manner of actuating my process for themanufacture of artificial silk from cellulose described in my patentapplication Ser. No. 443,655 filed July 15, 1908, of which the presentapplication is a division and which has for its object to reduceconsiderably the duration of the'operations, incident to its manufactureand t e cost of the product, and at the same time produce an articlesuperior to thatv at present made.

Referring to the drawings in which like parts 'are'similarly designated:Figure 1 is a longitudinal vertical section and Fig. 2. is a transversevertical section of the vessel in which the cellulose is dissolved.'Fig. 3 is a view partly in longitudinal section showing the filamentforming device. Fig. i is an enlarged view in section, of a tube for'contannng the hardenmg liquld. Flg. 5 IS a View partly in sectionshowing the manner of forming, winding and washing the filaments.

In carrying outmy invention I dispense with the customary washing of thecellulose in caustic soda, chlorin or other solution of oxidizingagents, that have for their object to render the cellulose more solventin the cupro-ammonium solvent of the cellulose known in the trade asSchweitzefissolution.

According to my invention I wash the cellulose one or more times inWater and expel the excess of water by compressing 1t in a suitablepress or in any other manner and then card the same.

The cellulose-is then ready to be dissolved and is placed in a suitablevessel containing at its bottom the cupro-ammonium solution and at itsto the cellulose. Such a vessel suitable for carrying. out the presentinvention is shown in Figs. 1 and 2 and comprises a lower cylindricalsection 1 in which is mounted a shaft 2 provided with agitator blades 4.and a pulley 3 mounted on shaft 2 for driving the same. Below theagitator blades I form in the cylindrical portion 1 a depression orgutter l in which lies a pipe 5 supplied with compressed air, said pipehaving lateral exit orifices '6. Above the cylindrical por-, tion is achamber 7 provided preferably with a rotatable bottom comprising a shaft10 on which is mounted a number of vanes 8. The shaft 10 isprovided witha suitable crank 9 or equivalent device for rotating the same and bydoing so the cellulose can be uniformily fed into the solutionchamber 1. The entire vessel is closed b a tight cover having an exitpipe 11 whicl is preferably conducted to an absorbent of ammonia. Thecarded cellulose containing some moisture isplaced in the chamber 7 onthe rotatable bottom thereof. Compressed air is forced through the pipe5 into the cupro-ammonium solution which is agitated by the blades 4 andsome of the ammonium into the liquid solvent by rotating by means of thecrank 9' the vanes 8 and is constantly stirred therein by the agitatorblades 4.

Heretofore the solution of the cellulose in the cupro-ammonium liquorhas been carried out at a low temperature and such temperature has beenmaintained somewhere in the neighborhood of six degrees'centigrade. Ihave found that it is not necessary. to provide special cooling meansfor the solution vessel. A sufficient low degree of temperature beingmaintained by the passage of the compressed air coming from the tube 5and flowing through the cupro-ammonium solution, a portion of theammonia contained in this latter is evaporated thus realizing thedesired lowering of the temperature of the cupro-ammonium solution. Theaunnonium gases issuing from the cupro-ammonium solution are carriedupward by the air forced through pipe 5 and orifices (3 past the movablebottom 8 into the body of the cellulose contained in chamber 7 andsaturates themoist cellulose with ammonium. This renders the cellulosereadily attackable by the cupro-ammonium solution and prevents the moistcellulose contained in the reservoir 7 from precipitating the copperoxid from the contained in the cellulose and thereby retard considerablythe operation. Moreover the further-incoming air causes a portion of theammoniaabsorbed by the cellulose to evaposulfuric and hydrochloric acid,in such quan-.

rate and produces therefore a cooling of this latter, which is thenready to be brought into contact with the cupro-ammonium solution below,which is also cooled at the desired degree. This is obtained by turningthe rotatable bottom 8 and then causing the cellulose to fall'into thechamber 1. By the.

action of the aqitator blades 4 a spinable solution of celliilosecontaining from 940% of cellulose will. be obtained in a couple ofhours. The residue of the ammonium gases having passed through thevessel 7 passes out through pipe 11 into a suitable collector not shown.The colloidal solution of cellulose thus obtained is filtered through afilter of any desired construction and is then caused to pass underpressure through capillary orifices where it encounters an acidcoagulant, This coagulant consists, as described in my patentapplication SenNo. 443,655 above referred to, of a-mixture of titiesthat the total acidity of the bath be suflicient to transform entirelyinto salts the ammonia and the copper introduced in the stirringcylinder; thus the greatest economy is obtained and the work ofrecuperation is reduced to a minimum. The colloidal solu tion ofcellulose after filtering is forced by means of the pressure of the airor gravity from tanks "(not shown), through a pipe 13 which connects thetanks to a container 12 provided with nipples 14 on which" are mountedfilament formers 16 having capillary tubes 17 and controlling valves 15.

Mounted on each of the filament formers are glass tubes 18 provided withsuitable pack-- ing rings 19 at their lower ends. In these glasscylinders are contained the coagulant, the capillary tubes 17 projectingabove the lower ends of said tubes and the inlet pipes 18 therefor.

\Vhen the apparatus works, the coagulant is fed into them at connection18 rises in the tubes 18 and overflows at b. When one of the capillarytubes 17 cannot work, the discharge I) is closed and the discharge a isopened; the coagulant is thus discharged without rising in the tube 18.The filament being of less gravity than the coagulant and being forcedunder pressure through the capillary tubes, rises to the surface of thecoagulant. It is then passed over a guide drum positioned so that it istangent to the center lines of the tube 18. The filament then passesover a guide roll 0 and between a drum 2i and a bobbin 20 being woundupon said bobbin. The bobbin is immersed in, running water contained ina suitable tank preferably lead lined. The drum 21 is driven and rotatesthe bobbins by means ofperipheral friction extended by drum '21 not onlateral end disksor other parts of the bobbin but on the thread itselfwhile being wound on the bobbin. This permits the maintenance of theuniform thickness imparted to the filaments by the drawing drum 23 andthe thread is always equally and constantly titrated. Drums 21 and 23are necessarily of the same diameter and perform the same number ofturns or otherwise the thread would notbe wound on the bobbin regularlyand tension would be placed on the filament. after it was coagulatedwhich would be apt to break it if 21 were run faster than 23'. The drum23 serves toplace' tension on the-thread as it is being formed and theamount of tension determines the thickness of the filaments. After thebobbins 20 have a filament wound on them of a thickness from 10 to 15millimeters they are removed while. still moist to a suitable twistingmachine where they are twisted into threads and Wound into skeins. WVhendried under tension the-brilliancy is maintained even after subsequentwashing. I claim:

1. In an apparatus of the character de-- scribed, a closed chamber,means for supplying compressed air to the bottom -'o. f the chamber,revoluble agitator blades mounted in the latter above the air supply, arotatable platform mounted in the chamber above saidblades for thereception of the moist'cellulose, and a pipe at. the top of said chamberfor the discharge of the ammonia.

2. An apparatus of the character described comprising a closed chamberhaving a lower cylindrical portion provided witha gutter in its bottom,a perforated pipe mounted in said gutter to supply air under pressure tothe cupro-ammonium solution contained in said cylindrical portion, ahorizontal rotatable shaft mounted in the latter, agitator blades on theshaft extending into the solution,a revoluble platform for the receptionof moist cellulose mounted in the chamber above said blades andpartially separating the lower part of the chamber from the upper part,means outside the chamber for revolving the platform. and a pipe at thetop of the chamber for the discharge of ammonia from the latter. I

In testimony that I claim the foregoing as my invention, I have signedmy name in presence of two subscribing witnesses.

' GTUSEPPE GUADAGNI. W'itnesses Fnaxonsco Sworn, Cnsoa TAoLos

